In 1924 the National Union of South African Students (NUSAS) was founded aimed at representing and promoting the interests of university and college students. NUSAS was open to students of all races. At the organisation first inaugural conference in Bloemfontein in 1924 the following universities were represented: Pretoria, Natal, Witwatersrand, Rhodes, Bloemfontein, Potchefstroom and Cape Town.

The Confederation International des Students (C.I.E.) which was founded in 1919 in Strasbourg, France to represent the interest students internationally inspired the formation of a national union of students of that magnitude in Britain in 1920. This in turn influenced students in Commonwealth countries to follow suit and South Africa was no exception. Leo Marquard, who was fortunate enough to have attended C.I.E. congresses in Europe, was instrumental in the formation of NUSAS. In 1926 NUSAS was involved in an overseas exchange programs by its executive members in order to learn more about the running of the organisation. In 1927 a student parliament was founded in Durban and this structure was run like a political party. Membership of the new structure within NUSAS was confined to White students. It was believed they were better position to engage government in dialogues than their Black counterparts. In the early 1930s NUSAS was affected by the growing feeling of the Afrikaner nationalism.

The Afikaanse Studentebond (A.S.B.), which was in existence since 1917 felt that for full cultural and political recognition for Afrikaans, Afrikaner students needed to re-think their position in NUSAS, as a wider national body would no serve their purpose. In 1933 a more political Afrikaner body called Afrikaanse Nationale Studentebond (A.N.S.B.) was established. After the formation of A.N.S.B. students from Universities of Bloemfontein, Potchefstroom and Pretoria withdrew from NUSAS. Stellenbosch was no convinced of the decision taken so it continued with its membership in NUSAS. The University of Fort Hare in 1935 posed a serious challenge to the hierarchy of NUSAS as it wanted to join the organisation on the ground that it was inclusive to all races. University of Fort Hare was and still a Black dominant institution and their request for admission was rejected. It was then the University of Stellenbosch came to a realization that without University of Pretoria, Bloemfontein and Potchesfroom the objectives of NUSAS could no be attained. The institution was wary of trying to create a national unity amongst university and colleges without support from others.

University of Stellenbosch duly cut its ties from NUSAS and this completed the split between Afrikaans and English speaking universities. In 1945 University of Fort Hare became a member of NUSAS. It was only after the admission of Fort Hare and Non-White section of the University College of Natal in the 1940s that NUSAS became a non-racial organisation. NUSAS started to be vocal and denounce apartheid and its legalisation. This in turn drew fierce anger from politicians. In the 1960s there were direct confrontation between government and the NUSAS leadership, which at some instances resulted in detention, banning, deportation and withdrawal of passports for the office-bearers. NUSAS's permanent office, which was situated in Cape Town, was fundamental in practical benefits and services of the student community. Each year an overseas tour was organised. In 1953 NUSAS was a member of International Union of Students (I.U.S.) but withdraw its membership due to Communist dominance. In 1960s NUSAS handled 60 overseas scholarships and awarded 25 medical scholarships of its own. Local centres of NUSAS used to organise vocational part-time employment for its members.

NUSAS since its inception was awarded over R47 000 in interest-free loans for the needy students and this was payable in the period of ten years. NUSAS was also active in to other social responsibilities such as educating prisoners about moral of the society, released prisoners, counseling children of prisoners, adult education of Blacks and feeding schemes for the poor of all races. It was amazing how NUSAS structured itself in the late 1960s, the Student Representative Council in each an every member university sent a delegate to the organisation central body, which decided on policy and elects an executive council. Whilst there were always a small minority of 'radical' students heavily influenced by Marxist ideas on campus, it was not until the arrival of Rick Turner from the Sorbonne in late 1967, that the ideas of 'new left' thinkers really found a voice within this group. The dissatisfied members of I.U.S. formed the International Student Conference in 1964 but it had to dissolve in 1968 due to internal problems.

In 1970 Black students led by Steve Biko broke away from NUSAS to form South African Students Organisation (SASO). The reason why this happened was that Black intellectuals within NUSAS were against White domination and its failure to act in a radical manner in issues affecting Black students. This was also driven by the incident, which happened at Rhodes University in July 1967 when Black delegates were prohibited to use the same facilities as their White counterparts. In 1972 NUSAS claimed it had 29 000 members in eleven institutions of higher learning including in those that had withdrawn from the organisation. In the aftermath of Soweto Uprising in 1976, NUSAS tried to make amends with SASO by trying to be more vocal against the government in so far as change in education system was concerned. This is so because SASO felt that NUSAS was used and sponsored by government in most of its activities. In 1983 NUSAS forged an alliance with the newly formed United Democratic Fronts (UDF). Most importantly this alliance meant that the Congress of South African Students (COSAS) was in alliance with NUSAS as it regarded itself as the student wing of the UDF. In April 1986 NUSAS arranged a meeting with the banned African National Congress (ANC) in Harare, Zimbabwe to discuss among other thing the active participation of the ANC in finding a solution for South Africa's problems. NUSAS also called for the unconditional release of Nelson Mandela. NUSAS with this radical stance it took endured itself to the brutality and harassment of the South African security branch. In the late 1980s NUSAS's offices were put under surveillances and it became difficult to conduct their day-to-day activities. With the banning of the UDF in 1989 it became difficult for NUSAS to have an ally they could openly challenge the South African government due to its apartheid policies. Realising that a milestone was achieved with the unbanning of political parties and the start of negotiations for a new democratic South Africa, NUSAS felt it had done a lot since its inception in 1924. On 2 July 1991 the organisation felt the need to dissolve in order to face the challenges awaiting them separately.